At frisians every miner which is better gets goldmine symbol and at coalmine it is also at a normal miner.

I don't understand fully what is the problem. What I could confirm is that the menu.png for most frisian workers isn't very nice, as the ware symbol (e.g. iron ore for normal miners and gold ore for master miners) is drawn over the worker symbol in such a size that it most times is completely hiding the worker.
What I can't confirm that the icons are mixed in the mines. Could you provide a screenshot of the situation?

I think that Frisian worker symbols are the best by far, because you can easier recognize what they stand for. But if you want to build a Frisian building it's harder than with other tribes, because they look more similar.

“It's a threat to our planet to believe that someone else will save it.” - Robert Swan

If you go into the lobby and if there is a match X already running, the metaserver says "match X is now available", which is absolutely incorrect because nobody can join. This could confuse new players...

“It's a threat to our planet to believe that someone else will save it.” - Robert Swan

Frisian Woodcutters don't go to trees in unknown terrain (while other woodcutters do, at least Atlantean ones). Is this a bug?

At least there should be no difference between the tribes as the code for both woodcutters is identical in the relevant parts. Only thing that might differ is visibility might differ. Need to check that.

More bugs:

"census" and "statistics" get hidden behind objects (like trees and other buildings). Soldier stats also get hidden, both of this is very annoying.

I believe this was fixed but the fix was removed due to being unstable and producing other issues (blinking buildings) which were even more annoying. Our z-layering system seems to be a bit tricky.

The soundfiles itself don't have changed, although with the TADA branch only the smith_00 and toolsmith_00 sound has been changed. However there are smith_01 and smith_02 as well as toolsmith_01 sounds that might be played instead (perhaps due to variety reasons?)